2121218101 has 2 divisors, whose sum is σ = 2121218102. Its totient is φ = 2121218100.

The previous prime is 2121218093. The next prime is 2121218111. The reversal of 2121218101 is 1018121212.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 2095259076 + 25959025 = 45774^2 + 5095^2 .

It is a cyclic number.

It is not a de Polignac number, because 2121218101 - 2³ = 2121218093 is a prime.

It is an alternating number because its digits alternate between even and odd.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2121218111) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1060609050 + 1060609051.

It is an arithmetic number, because the mean of its divisors is an integer number (1060609051).

Almost surely, 2^2121218101 is an apocalyptic number.

It is an amenable number.

2121218101 is a deficient number, since it is larger than the sum of its proper divisors (1).

2121218101 is an equidigital number, since it uses as much as digits as its factorization.

2121218101 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 64, while the sum is 19.

The square root of 2121218101 is about 46056.6835649290. The cubic root of 2121218101 is about 1284.8776500869.

Adding to 2121218101 its reverse (1018121212), we get a palindrome (3139339313).

The spelling of 2121218101 in words is "two billion, one hundred twenty-one million, two hundred eighteen thousand, one hundred one".